Re: CM11A hangup: Any better products?

[nobody@xxxxxxxxxxxx (Dave Houston)]

The CM11A has 2 batteries which are used _solely_ to run the RTC when there
is no 60Hz power. The CM11A PIC uses a resonator but also uses a discrete LC
oscillator for the PLC carrier. CM11As do not keep very accurate time when
running on batteries which is why the CM11A starts sending a "power fail
poll" as soon as 60Hz power is restored.

Joerg <notthisjoergsch@xxxxxxxxxxxxxxxxxxxxx> wrote:

>Hello Dave,
>
>> The CM11A keeps time using the 60Hz line frequency. The RR501 does not keep
>> time.
>
>It can't do it always. Mine also keeps the time when the power is out
>and it runs on the four backup batteries. One of them that I programmed
>for a friend even kept time while sitting in the trunk of his car for
>weeks. That is nearly impossible with LC.
>
>Regards, Joerg
>
>http://www.analogconsultants.com